The first use of 'the Nobel disease' that I am aware of occurred in one of David Gorski's Science-Based Medicine blogs where he not only discusses several instances of the affliction but attributes the expression to "a few wags." Gorski describes the affliction as "a tendency among Nobel Prize recipients in science to become enamored of strange ideas or even outright pseudoscience in their later years."

There are many reasons why smart people sometimes believe dumb things. The smarter one is the easier it is to see patterns, fit data to a hypothesis, and draw inferences. The smarter one is the easier it is to rationalize, i.e., explain away strong evidence contrary to one's beliefs. Also, smart people are often arrogant and incorrectly think that they cannot be deceived by others, the data, or themselves.

Is the Nobel disease a real disease and does it infect an unusually large percentage of Nobel laureates? It's about as real and infectious as the MD disease: an affliction of certain medical doctors that causes them to embrace strange or scientifically unsound ideas, even outright pseudoscience, not necessarily later in life.

It is not surprising that it is easier to find a longer list of MDs than of Nobel laureates defending wacky ideas. The former grandly outnumber the latter. But the point to draw from all of this is the same: being an authority in one field does not make one an authority in any other field. Many people love to cite a Nobel laureate, a scientist, or an MD to support their position, but once an expert begins to make claims outside of his or her field of expertise, the authority is no greater than yours or mine.

There are, of course, as many "diseases" of this type as there are types of experts or authorities. I'll let others construct those lists, especially the list of PhDs in philosophy who defend wacky ideas.